[U-Boot] [PATCH v2] ppc/85xx: PIO Support for FSL eSDHC Controller Driver
Wolfgang Denk
wd at denx.de
Tue Sep 22 20:41:44 CEST 2009
Dear Dipen Dudhat,
In message <1252589856-4970-1-git-send-email-dipen.dudhat at freescale.com> you wrote:
> On some Freescale SoC Internal DMA of eSDHC controller has bug.
>
> So PIO Mode has introduced to do data transfer using CPU.
> In PIO mode data transfer performance will be degraded by a large extent.
>
> Note:
> In PIO mode multiple block read/write requires delay to complete the transfer.
Does that mean you just delay, i. e. you do not check for some ready
state?
...
> --- a/include/fsl_esdhc.h
> +++ b/include/fsl_esdhc.h
> @@ -86,6 +86,7 @@
> #define PRSSTAT_CDPL (0x00040000)
> #define PRSSTAT_CINS (0x00010000)
> #define PRSSTAT_BREN (0x00000800)
> +#define PRSSTAT_BWEN (0x00000400)
> #define PRSSTAT_DLA (0x00000004)
> #define PRSSTAT_CICHB (0x00000002)
> #define PRSSTAT_CIDHB (0x00000001)
> @@ -117,6 +118,7 @@
> #define XFERTYP_DMAEN 0x00000001
>
> #define CINS_TIMEOUT 1000
> +#define MAX_TIMEOUT 100000
MAX_TIMEOUT is a very generic name, please chose a more specific one
so interactions with other code are prevented. (Also, TIMEOUT itself
already means a maximum time, so MAX_TIMEOUT is a tautology.)
Best regards,
Wolfgang Denk
--
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Very ugly or very beautiful women should be flattered on their
understanding, and mediocre ones on their beauty.
-- Philip Earl of Chesterfield
More information about the U-Boot
mailing list